This invention relates to a fuel filtering device used for a Diesel engine mounted on a motor vehicle.
In connection with a Diesel engine, the engine mounted on a motor vehicle is operated on a so-called light oil which is usually higher in pour point than gasoline or petrol. Accordingly, the light oil will lose its fluidity and produce wax like material at temperatures lower than -10.degree. C., which wax like material will become attached onto the surface of a filtering element of a fuel filter to clog the filtering element. Such clogging may also rise in the case where the fuel filter is installed at a section of the motor vehicle is liable to be cooled with cold air during vehicle operation. The filter element clogging increases the flow resistance of fuel passing through the filter element, and leads finally to a serious drawback in that the fuel will not be supplied smoothly to the engine.